Transition to the solid state

The physical-chemical properties of a supercritical fluid are between those of liquids and gases supercritical fluids (SCFs) indicate the fluid state of a compound in pure substance or as the main component above its critical pressure (pc) and its critical temperature (Tc), but below the pressure for phase transition to the solid state, and in terms of SCF processing, a density close to or higher than its critical density. 

Investigation of thermodynamic behavior of monolayers formed from mixtures of bis[2-(n-hexadecanoyl)ethyl]methyl(4-vinylbenzyl) ammonium chloride (1) and dioctadecyl-dimethylammonium bromide (5) serves as the second example [116]. The determined surface-pressure/surface-area isotherms of mono-layers prepared from (1) and (5) and from their mixtures are given in Fig. 8. The isotherms showed the expected behavior following the liquid state there was a transition to the solid state in the region of 20-36 mNm 1. This transition was characterized by a pressure, and by a corresponding area, Aj. All isotherms intersected in the vicinity of 30 mNm-1 and, at surface-pressure/surface-area... 

The thermoplastic semifinished part production can be divided into the following processes impregnating, consolidating, and transitioning to the solid state. During processing, the input materials (fiber and matrix) depend on the process-required control variables Temperature T, time t, and pressure p, which will then determine the resulting properties of the semifinished parts [2]. 

The actual formation of the fibers and films in a spinning or extrusion process takes place during coagulation of the lyotropic solution. In this process step a phase transition to the solid state is induced by a non-solvent. The conditions of the coagulation process, e.g. the concentration of the polymer solution, the composition and the temperature of... 

---